Forensic Speech Enhancement: Toward Reliable Handling of Poor-Quality Speech Recordings Used as Evidence in Criminal Trials

Abstract

This paper proposes an innovative interdisciplinary approach to evaluating the effectiveness of forensic speech enhancement (FSE). FSE faces unique challenges arising from a range of factors, from poor recording quality, highly variable conditions from case to case, and content uncertainty. Despite these difficulties, FSE is commonly admitted in court, and can significantly influence the outcome of criminal trials. Current FSE practices are hindered by unrealistic expectations from courts, which often assume that enhanced audio inherently clarifies content. In fact, FSE can have the undesired opposite effect, potentially resulting in unfair prejudice, when, for example, it increases the cred..